Machine for the production of groups of roll products

ABSTRACT

A machine for the production of groups of roll products includes a second unit ( 5 ) for turning and grouping a plurality of product groups ( 4 ) and comprising: an endless drive system ( 6 ) mounting a plurality of paddles ( 7 ) protruding radially from the path line (P 6 ) of the drive system ( 6 ); each paddle ( 7 ) forming, with the next one, a space (S) for receiving a product group ( 4 ) and turning it through at least a right angle (α); in the second unit ( 5 ) each paddle ( 7 ) consists of an element divided into an upper section ( 16 ), constituting a part that supports and pushes the groups ( 4 ) of products, and an open lower section, and means ( 17 ) are provided for adjusting the supporting depth (H 7 ) of the product groups ( 4 ) on the paddles ( 7 ) according to the type of configuration, and act at least along an arc-shaped section of the paddle ( 7 ) drive path (P 6 ) between the above mentioned product group ( 4 ) pickup area, where each paddle ( 7 ) lies in the same plane as the first unit ( 3 ), and the position of the paddle ( 7 ) when it has been turned through the above mentioned right angle (α).

BACKGROUND OF THE INVENTION

This invention relates to a machine for the production of groups of rollproducts, in particular, but without limiting the scope of theinvention, rolls of toilet paper or kitchen paper.

It is very well known that machines of this kind for producing groups ofroll products consist of a plurality stations, located in line along themachine itself, where the products are manipulated and divided up toform first the groups, of products and then the final packages.

In practice, the stations basically comprise:

a unit for feeding the roll products;

a unit for dividing the roll products into groups;

a unit for wrapping and sealing the groups of products.

In addition to these, the production line may comprise a series ofstations for conveying and positioning a plurality of these groups (alsoreferred to as batch—which may include one or more wrapped groups ofproducts) for the end of line stations where the batches can be baggedand palletized, ready for storage or transportation.

More specifically, the structures that prepare the products for the endof line stations normally comprise the following, in current machines: asystem for conveying and, if necessary, diverting the products (withbelts and related comb pushers); downstream of this system, there is aproduct straightening unit that turns each group of products by 90° andto form batches of product groups that are advanced by other combpushers towards an end bagging machine (usually in a directionperpendicular to the direction in which the batches are fed to thestraightening unit) or towards units for picking up and palletizing thegroups of products.

This specification is concerned in particular with the straighteningunit, which may comprise the following (see FIGS. 1 and 2 illustratingtwo such units as known in prior art: a pair of parallel endless chainsC trained around pairs of power-driven toothed wheels R; the chains Care associated with a plurality of paddles P, protruding radially fromthe chains C, for picking up, tipping up by 90° (from a “lying down” toan upright position) and moving the incoming groups of products G fromthe conveyor system. Each paddle P is substantially L-shaped to be ableto stably accommodate one side L1 and the base L2 of the incoming groupG and to turn the latter by ninety degrees.

The side of the paddle P that accommodates the base L2 is linked to apair of guides S associated with the pair of chains C.

As clearly shown in FIGS. 1 and 2, the number and size of the paddles Pmounted on the chains C varies in accordance with the size andconfiguration of the product groups G made by the machine.

At present, roll products come in several different diameter sizes andat least two different types of packs (single or double layer) whichmeans that many sets of paddles P of different widths are required tohandle all pack sizes (for current pack sizes, five different sets areused, distinguished by the different colors of the guides).

To this must be added the fact that the pack sizes vary in heightaccording to the packing style, that is to say, the height may be thatof a single product or the sum of different products placed one afterthe other within the same group of products.

In this case, too, the paddle dimension L1 must vary in length accordingto the product group G formed by the machine. At present, the productgroups G available on the market come in seven different lengths.

The products can be variously combined to form at least thirty-fivedifferent configurations which the straightening unit must be able tohandle.

The changeover procedure to be performed on this unit consists of thefollowing steps: stopping the machine; removing all the products of theold configuration; manually disconnecting all the paddle P guides S fromthe chains C; and positioning another set of paddles P for the newconfiguration, also performed manually by the operator.

As may be inferred from this summary description, the changeoverprocedure for a straightening unit is a time-consuming, laborious taskand, taking into account that changeovers in machines of this kind arequite frequent, that adds up to a considerable amount of down time,which in turn means a significant reduction in machine productivity as awhole.

SUMMARY OF THE INVENTION

The aim of this invention is to overcome these disadvantages byproviding a machine for the production of roll products equipped with aproduct group straightening unit that is extremely versatile and allowschangeover to be performed quickly and without necessitating manualoperations on the unit itself.

According to the invention, this aim is achieved by a machine for theproduction of groups of roll products comprising the technicalcharacteristics described in one or more of the claims herein.

BRIEF DESCRIPTION OF THE DRAWINGS

The technical characteristics of the invention, with reference to theabove aims, are clearly described in the claims below and its advantagesare apparent from the detailed description which follows, with referenceto the accompanying drawings which illustrate preferred embodiments ofthe invention provided merely by way of example without restricting thescope of the inventive concept, and in which:

FIGS. 1 and 2 are schematic side views showing two different operatingconfigurations of a prior art station in a machine for the production ofroll products;

FIG. 3 is a schematic perspective view from above of a part of themachine for producing product groups according to the invention;

FIGS. 4 and 5 are, respectively, a schematic side view and a schematictop plan view of the detail E from FIG. 3, that is to say, of a unit forstraightening the groups of products according to the invention, in afirst operating configuration;

FIGS. 6 and 7 are, respectively, a schematic side view and a schematictop plan view of the detail E from FIG. 3, that is to say, of a unit forstraightening the groups of products according to the invention, in asecond operating configuration;

FIG. 8 is a schematic front view, with some parts cut away, of thestraightening station of FIG. 4;

FIG. 9 shows a scaled-up detail from FIG. 4 in a schematic side view;

FIG. 10 shows a scaled-up detail from FIG. 6 in a schematic side view;

FIG. 11 is a schematic side view, with some parts cut away in order tobetter illustrate others, showing an alternative constructional detailof the straightening station illustrated in the drawings listed above;

FIG. 12 illustrates another embodiment of the straightening station ofFIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the accompanying drawings, and in particular FIGS. 3to 7, the machine according to the invention is used to make groups 4 ofproducts, especially but without restricting the scope of the invention,groups of roll products for household or bathroom use.

Each of the groups 4 consists of a plurality of products 2, arranged ingroups defining a configuration (that varies in accordance withproduction requirements, as we shall see in more detail below), wrappedin a sheet of film and closed, for example by heat-sealing.

The forming of the individual groups 4 of products is not described orillustrated in this specification since it is accomplished by knownstations and units that do not strictly form part of this invention.

The part of the machine which this specification is concerned with andwhich is labeled 1 in its entirety, comprises at least the followingalong a feed line A:

a first unit 3 for conveying the product groups 4 one after the othertowards

a second unit 5 for picking up, turning and grouping a plurality ofproduct groups 4.

The first unit 3 may be constructed in different ways, oneconstructional form being illustrated purely by way of example in FIG.3, and enables the groups 4 to be transferred from the stations wherethe groups 4 are made to the second unit 5 and, hence, to the end ofline stations which are not illustrated or described here since they areof known type and do not fall within the scope of this invention.

The first unit 3 may consist of a pair of belts 3 a and 3 b positionedat an angle to each other to form a system for turning the productgroups 4 through 90°. The product groups 4 are moved (and, if necessary,two or more groups are placed side by side) by comb pusher means 3 c.

The second unit 5, consisting of a unit for “straightening” the productgroups 4, is located downstream of the first unit 3.

The second unit 5 (see FIGS. 3 to 7) comprises a motorized endless drivesystem 6 mounting a plurality of paddles 7 protruding radially from thepath line P6 of the drive system 6; each paddle 7 forms, with the nextone, a space S for receiving a product group 4 at a position where thepaddle 7 is co-planar with the first unit 3, or more specifically, withthe upper section 3 b (see FIG. 4) and is turned through an angle α ofat least ninety degrees in the direction, indicated by the arrow S6, inwhich the drive system 6 advances.

Once turned, the product groups 4 are positioned side by side on theupper section of the drive system 6, and are then expelled from therespective spaces S by comb pusher means 100 which move them towards theend of line units (not illustrated).

As shown in FIGS. 4 to 11, in the second unit 5:

each of the paddles 7 consists of an element divided into an uppersection 16, constituting a part that supports and pushes the groups 4 ofproducts, and an open lower section; and

means 17 are provided for adjusting the supporting depth H7 of theproduct groups 4 on the paddles 7 according to the type ofconfiguration, and act at least along an arc-shaped section of thepaddle 7 drive path P6 between the above mentioned product group 4pickup area, where each paddle 7 lies in the same plane as the firstunit 3, and the position of the paddle 7 when it has been turned throughthe above mentioned right angle α.

More specifically, (with reference also to FIGS. 8 to 10), each paddle 7may consist of a flat member having the shape of an upturned U where thetwo legs 14 and 15 are connected to the drive system 6, and where theconnecting section 16 of the U defines at least a part of the space forpicking up and containing the product groups 4 and a central opening 16g.

The U shape of the paddles 7 described in this specification is apreferred non-limiting embodiment of them and, as shown in FIG. 12, thepaddles 7 might not have the leg 14 and might be connected by the otherleg only to a single drive system 6 a or 6 b, thus forming a rotated Lshape: this would create a unit 5 with a lighter structure (without oneof the wheel and chain drive systems) while maintaining the same levelof operating efficiency.

The characteristic constructional form of each paddle 7, combined withthe fact (as described in more detail below) that there is a set numberof paddles 7, makes it possible to define this supporting depthadjustment on the second unit 5.

This adjustment is necessary because, besides the above mentionedconfigurations, the groups 4 of products 2 may have a plurality ofadditional configurations defined by a second dimension H (longitudinaldimension of the group 4) defined by the height or the sum of superposedheights of the wrapped roll products 2, and included at least between athird, minimum sub-configuration LA3 in which each product 2 has a firstheight H1 and a fourth, maximum sub-configuration LA4 in which eachproduct 2 has a second height H2 that is greater than the first heightH1 (see FIGS. 9 and 10).

More specifically (again see FIGS. 9 and 10), the means 17 for adjustingthe supporting depth H7 of each paddle 7 may comprise, in a firstembodiment:

an arc-shaped surface 18 positioned and operating in the arc-shapedsection of the path P6 at the opening 16 g defined by the U shape ofeach passing paddle 7;

a straight, static surface 19 forming the base of each containment spaceS and connected to the arc-shaped surface 18;

first actuating means 20 for moving the arc-shaped surface 18 along theopenings 16 g of the paddles 7 between two or more operating positions(see arrows F20), according to configurations, included between a first,advanced minimum depth operating position, where the arc-shaped surface18 is substantially in contact with the wall 16 of the passing paddles7, and a second, retracted, maximum depth position where the arc-shapedsurface 18 is away from the passing walls 16, so as to vary thesupporting depth H7 of the passing paddles 7 according to the abovementioned third and fourth sub-configurations LA3 and LA4.

Obviously, in this situation, since the straight surface 19 ispositioned at a fixed distance, it must be positioned at a distance H3from the paddle 7 wall 16 that is smaller than the height H1 of thethird, minimum sub-configuration LA3 so as to always allow contact ofthe wall 16 with any configuration after turning and then lowering theproduct group 4 along the wall 16 of the paddle 7 until contact with thesurface 19.

In an alternative embodiment (illustrated schematically in FIG. 11), themeans 17 for adjusting the supporting depth H7 of each paddle 7 may actboth along the arc-shaped section and along a straight operating sectionof the path P6, that is to say, along the active sections of the secondunit 5, so that the supporting depth H7 of each paddle 7 remainsconstant between the area where the product groups 4 are received andthe area where the product groups 4 are expelled.

In this embodiment, the means 17 for adjusting the supporting depth H7may comprise:

the first arc-shaped surface 18 positioned and operating in thearc-shaped section of the path P6 at the opening 16 g defined by the Ushape of each passing paddle 7;

a second, straight, mobile surface 19 forming the base of eachcontainment space S and connected to the arc-shaped surface 18;

actuating means 20 for moving both the arc-shaped surface 18 and thesecond surface 19 along the passing openings 16 g between two or moreoperating positions, according to the configurations, included betweenthe first, advanced minimum depth operating position and the second,retracted, maximum depth position.

In this alternative embodiment, the actuating means 20 may be dividedinto:

first actuating means 20 a acting on the first, arc-shaped surface 18 insuch a way as to move it between the operating positions (see arrows F20a); and

second actuating means 20 b acting on the second, straight surface 19 insuch a way as to move it in height between the operating positions insynchrony with the first actuating means 20 a, while keeping the secondsurface 19 perpendicular to the passing paddles 7 at all times (seearrows F20 b).

To keep the transition between the two surfaces 18 and 19 smooth, thesurfaces 18 and 19 themselves are connected to each other by a third,flexible transition surface 21, with tubular cross section, which formsa telescoping sliding connection between the respective ends of the twosurfaces 18 and 19, joined to the third surface 21 itself and permittingthe double adjustment of the first and second surfaces 18 and 19 bycausing the two surfaces 18 and 19 to slide relative to the third,flexible tubular surface 21 (see arrows F21).

Advantageously, the actuating means 20, 20 a, 20 b can be activated bythe machine 1 control unit 13 so that all the adjustments describedabove are coordinated.

To enable all the above mentioned second configurations of the productgroups 4 included between the third and fourth sub-configurations LA3and LA4 to be picked up correctly:

the depth H16 of the wall 16 must be at least equal to the height of thethird, minimum sub-configuration LA3; and

the wall 16 and the first arc-shaped surface 18 in the second, retractedmaximum depth position must have a total depth H7 at least equal to thefourth, maximum sub-configuration LA4, that is to say, the sum of H16(fixed) and H18 (variable, starting from the lower end of the wall 16)must be equal to the fourth, maximum sub-configuration LA4.

The spacing between the configuration depth H7 adjustment surface 18 andthe paddles 7 means that the surface 18 also acts as a means forrelieving the stress created by the pressure on the packages alreadypositioned on the paddles 7 (applied by the product groups 4 positionedon the first feed unit 3).

This is possible because the control unit 13 can control the actuatingmeans 20, 20 a and 20 b in such a way as to enable a forward movement ofthe first, arc-shaped surface 18, past the predetermined height H,depending on the configuration, and then a guided return movement of thesurface 18 itself with the advancing product groups 4 so as to producesaid relief action during the feeding of the product groups 4themselves.

This enables the paddles 7 to rotate the product groups 4 more easilysince the paddle 7 does not have a base attached under it acting as abrake under the axial thrust of the product groups 4.

Still with reference to FIGS. 4 to 7, the second unit 5 also comprises:

a set number of the paddles 7;

a division of the paddles 7 into two distinct groups 7 a and 7 b, eachof the groups 7 a and 7 b being connected respectively to a first and asecond drive system 6 a and 6 b, in such a way that the paddles 7 of thetwo groups are positioned alternately along the endless path P6;

means 8 for adjusting at least one of the two groups of paddles 7—inthis case, the one labeled 7 a—relative to the other group 7 b, in sucha way as to define two different relative operating positions betweenthe two groups 7 a, 7 b of paddles 7.

In the first position, the paddles 7 of the two groups 7 a, 7 b areequally spaced to form a working containment space S1 (see FIGS. 4 and5), and in the second position, the paddles 7 of the two groups 7 a, 7 bare positioned close together in pairs to form a second workingcontainment space S2 (see FIGS. 6 and 7) that is larger than the firstcontainment space S1 defined by the first position.

In other words, irrespective of the plurality of possible configurationsof the product 2 groups 4 (which we will see in more detail below),there are only two positions that can be adopted by the paddles 7 —in aset number on the drive systems 6 a and 6 b—to define the transversaldimension of the spaces S.

More specifically, in the second operating position, only the group 7 bof paddles 7 defines respective spaces S for containing the groups 4 ofproducts 2.

Looking more closely at the details of the invention, the product groups4 may have any of a plurality of different configurations according to afirst (transversal) dimension LA and included at least between a first,single-layer configuration and a second, double-layer configuration ofwrapped products 2 (shown in FIGS. 5 and 7); each first and secondconfiguration being subdivided into two or more sub-configurationsdefined by a first, minimum sub-configuration LA1 in which each product2 has a first diameter D1, and a second, maximum sub-configuration LA2in which each product 2 has a second diameter D2 that is greater thanthe first diameter D1.

The two positions of the groups 7 a and 7 b of paddles 7 make itpossible to accommodate all the above mentioned configurations andsub-configurations.

More specifically, at the first operating position, each paddle 7 ofboth groups 7 a, 7 b forms a first working containment space S1, definedas the distance between two consecutive paddles 7, designed to permitthe passage and containment of the first configuration, including therespective sub-configurations between the first and the second, minimumand maximum sub-configuration LA1 and LA2 (again, see FIGS. 4 and 5).

At the second operating position, each paddle 7 of the group 7 b (fixed)forms a second working containment space S2, defined as the distancebetween the working containment paddle 7 and the next or precedingpaddle 7 placed side by side with the next or preceding workingcontainment paddle 7, designed to permit the passage and containment ofthe second configuration, including the respective sub-configurationsbetween the first and the second, minimum and maximum sub-configurationLA1 and LA2.

In short, the size of the spaces S1 and S2 delimited by the two possiblepositions of the groups 7 a and 7 b of paddles 7 must satisfy, for eachgrouping of single- and double-layer configurations, two essentialconditions: the spaces S1 and S2 must be able to accommodate the secondmaximum sub-configuration LA2 (maximum overall and diameter dimension ofthe product 2) and the first sub-configuration LA1 (minimum overall anddiameter dimension of the product 2) must not be able to turn round onitself (i.e. be positioned sideways or aslant) within the space S1 or S2as the paddles 7 move around and during subsequent expulsion by thepusher means 100.

Looking in more detail at the operating structure, the first and seconddrive systems 6 a and 6 b each comprise (see FIG. 8):

two pairs 9 a, 9 b of endless drive chains trained around two respectivepairs 10 a, 10 b of toothed wheels kinematically connected to each otherand to a single motor 11; the pairs 9 a, 9 b of chains mount the firstgroup 7 a and the second group 7 b of paddles 7, respectively;

the above mentioned adjustment means 8 operating between the two pairs 9a, 9 b of chains and the single motor 11.

Purely by way of example, without limiting the scope of the invention,the adjustment means 8 may comprise a mechanical clutch 12 positionedand acting on the drive system 6 a and designed to change between twoseparate states, in the first of which the clutch 12 simultaneouslytransmits drive to both the drive systems 6 a and 6 b, causing thegroups 7 a, 7 b of paddles 7 to move normally along the endless path P6,and in the second of which the clutch 12 does not transmit drive to oneof the drive systems, namely, the one labeled 6 b, so as to keep therespective group 7 b of paddles 7 stationary while the group 7 a ofpaddles 7 connected to the other drive system 6 a moves in such a way asto vary its relative distance from the other group 7 b of paddles 7between the two above mentioned relative operating positions (see arrowsF7 a).

The mechanical clutch 12 may be operated manually or automatically by amachine 1 control unit 13, represented schematically as a block in thedrawings.

The cascade connection with the toothed wheels of the two drive systems6 a and 6 b is not described in detail since it is of known type.

In a machine with this structure, therefore, the straightening unit canbe adjusted in two simple steps and without having to operate directlyon the paddles or to change the paddles every time changeover isrequired.

The straightening unit, therefore, comprises a set number of paddlesthat can be adjusted, even automatically, in just two steps:

the first step regards the transversal dimension (single or doublelayer, independently of the diameter of the products) between two paddlepositions (close together or spaced apart);

the other step regards the height of the products, adjusted using onlythe single arc-shaped section or the arc-shaped section and the mobilestraight section in order to vary the supporting height of the productgroups on the paddles, again quickly and easily and without having tosubstitute the paddles on the unit.

The straightening unit therefore fully achieves the aforementioned aimsthanks to a simple, optimized structure that enables changeovers to beperformed quickly and accurately without altering the basic architectureof the unit but optimizing and simplifying the cross adjustment systemon the many possible product group configurations.

This significantly reduces unit down time due to changeovers, withobvious benefits in terms of machine productivity as a whole.

The invention described has evident industrial applications and can bemodified an adapted in many ways without thereby departing from thescope of the inventive concept. Moreover, all the details of theinvention may be substituted by technically equivalent elements.

1. A machine for the production of groups of roll products packaged andwrapped in a sheet of wrapping film and each comprising a plurality ofproducts (2) grouped together in a dimensionally variable configuration;the machine (1) being of the type comprising, along a feed line (A), afirst unit (3) for conveying the product groups (4) one after the othertowards a second unit (5) for turning and grouping a plurality ofproduct groups (4) one after the other; the second unit (5) comprisingat least an endless drive system (6) mounting a plurality of paddles (7)protruding radially from the path line (P6) of the drive system (6);each paddle (7) being adapted to form, with the next one, a space (S)for receiving a product group (4) at a position where the paddle (7) isco-planar with the first unit (3) and to turn the groups through atleast a right angle (α) in the feed direction (S6) of the drive system(6); wherein: each of the paddles (7) in the second unit (5) comprisesan element divided into an upper section (16), constituting a part thatsupports and pushes the groups (4) of products, and an open lowersection; means (17) are provided for adjusting the supporting depth (H7)of the product groups (4) on the paddles (7) according to the type ofconfiguration, and act at least along an arc-shaped section of thepaddle (7) drive path (P6) between the above mentioned product group (4)pickup area, where each paddle (7) lies in the same plane as the firstunit (3), and the position of the paddle (7) when it has been turnedthrough the above mentioned right angle (α).
 2. The machine according toclaim 1, wherein each paddle (7) comprises an upturned U-shaped memberwhere the two legs (14, 15) are connected to the drive system (6) andwhere the connecting section (16) of the U constitutes the part thatsupports and pushes the product groups (4).
 3. The machine according toclaim 1, wherein each paddle (7) of the first group (7 a) and of thesecond group (7 b) comprises a rotated L-shaped member where thevertical leg (15) is connected to the respective drive system (6 a, 6 b)and where the horizontal leg (16) of the L forms at least a part of thespace for picking up and containing the product groups (4).
 4. Themachine according to claim 1, where the groups (4) of products (2) havea plurality of configurations defined by a second dimension (H) definedby the height or the sum of superposed heights of the wrapped rollproducts (2), and included at least between a third, minimumsub-configuration (LA3) in which each product has a first height (H1),and a fourth, maximum sub-configuration (LA4) in which each product (2)has a second height (H2) that is greater than the first height (H1), themachine being wherein each paddle (7) comprises an upturned U-shapedmember where the two legs (14, 15) are connected to the drive system(6), and where the connecting section of the U constitutes the wall (16)of the that supports and pushes the product groups (4); the means (17)being provided for adjusting the supporting depth (H7) of the paddles(7) according to the type of configuration and acting at least along anarc-shaped section of the paddle (7) drive path (P6), constituting theother part that supports and stops the product groups (4), between theproduct group (4) pickup area, where each paddle (7) lies in the sameplane as the first unit (3), and the position of the paddle (7) when ithas been turned through the right angle (α).
 5. The machine according toclaim 4, wherein the means (17) for adjusting the supporting depth (H7)of each paddle (7) comprise: an arc-shaped surface (18) positioned andoperating at least in the arc-shaped section of the path (P6) at theopening (16 g) defined by each passing paddle (7); a straight, staticsurface (19) forming the base of each containment space (S) andconnected to the arc-shaped surface (18); first actuating means (20) formoving the arc-shaped surface (18) along the openings (16 g) between twoor more operating positions, according to the configurations, includedbetween a first, advanced minimum depth operating position, where thearc-shaped surface (18) is substantially in contact with the wall (16)of the passing paddles (7), and a second, retracted, maximum depthposition where the arc-shaped surface (18) is away from the passingwalls (16), so as to vary the supporting depth (H7) of the passingpaddles (7) according to the configurations.
 6. The machine according toclaim 5, wherein the straight static surface (19) is positioned at adistance (H3) from the paddle (7) wall (16) that is smaller than theheight (H1) of the third, minimum sub-configuration (LA3).
 7. Themachine according to claim 4, wherein the means (17) for adjusting thesupporting depth of each paddle (7) are positioned on the arc-shapedsection and along a straight operating section of the path (P6), that isto say, along the active sections, so that the supporting depth (H7)remains constant between the area where the product groups (4) arereceived and the area where the product groups (4) are expelled.
 8. Themachine according to claim 7, wherein the means (17) for adjusting thedepth (H7) of each paddle (7) comprise: a first arc-shaped surface (18)positioned and operating in the arc-shaped section of the path (P6) atthe opening (16 g) in each passing paddle (7); a second, straight, uppermobile surface (19) forming the base of each containment space (S) andconnected to the arc-shaped surface (18); actuating means (20) formoving the arc-shaped surface (18) and the second surface (19) along thepassing openings (16 g) between two or more operating positions,according to the configurations, included between a first, advancedminimum depth operating position, where the first surface (18) and thesecond surface (19) are substantially in contact with the walls (16) ofthe passing paddles (7), and a second, retracted, maximum depth positionwhere the first surface (18) and the second surface (19) are away fromthe walls (16), so as to vary the supporting depth (H7) of each passingpaddle (7) according to the configurations.
 9. The machine according toclaim 8, wherein the actuating means (20) are divided into: firstactuating means (20 a) acting on the first, arc-shaped surface (18) insuch a way as to move it between the operating positions; and secondactuating means (20 b) acting on the second, straight surface (19) insuch a way as to move it in height between the operating positions insynchrony with the first actuating means (20 a) to keep the secondsurface (19) perpendicular to the passing paddles (7) at all times. 10.The machine according to claim 9, wherein the first arc-shaped surface(18) and the second straight surface (19) are connected to each other bya third, flexible transition surface (21), with tubular cross section,which forms a telescoping sliding connection between the respective endsof the first surface (18) and of the second surface (19), joined to thethird surface (21) itself and permitting the double adjustment of thefirst surface (18) and second surface (19) by causing the two surfaces(18, 19) to slide relative to the third, flexible tubular surface (21).11. The machine according to claim 5, wherein the actuating means (20,20 a, 20 b) can be activated by a unit (13) for controlling the machine(1).
 12. The machine according to claim 1, wherein the depth (H16) ofthe wall (16) is at least equal to the height of the third, minimumsub-configuration (LA3).
 13. The machine according to claim 1, whereinthe wall (16) and the first arc-shaped surface (18) in the second,retracted maximum depth position have a total depth (H7) at least equalto the fourth, maximum sub-configuration (LA4).
 14. The machineaccording to claim 1, wherein the control unit (13) controls theactuating means (20, 20 a, 20 b) in such a way as to enable a forwardmovement of the first, arc-shaped surface (18), past the predeterminedheight (H), depending on the configuration, and a guided return movementof the surface (18) itself with the product groups (4) so that, as theproduct groups (4) advance, the stress created by the pressure on theproduct groups (4) being positioned on the paddle (7) applied by theproduct groups (4) positioned on the first feed unit (3) is relieved.15. The machine according to claim 1, wherein the second unit (5)further comprises: a set number of paddles (7); a division of thepaddles (7) into two distinct groups (7 a, 7 b), each of the groups (7a, 7 b) being connected respectively to a first drive system (6 a) andto a second drive system (6 b), in such a way that the paddles (7) arepositioned alternately along the endless path (P6); means (8) foradjusting one of the groups (7 a) of paddles (7) relative to the othergroup (7 b), in such a way as to define two different relative operatingpositions between the two groups (7 a, 7 b) of paddles (7), namely, afirst position in which the paddles (7) of the two groups (7 a, 7 b) areequally spaced to form a working space (S1) for containing the productgroups (4) and a second position in which the paddles (7) of the twogroups (7 a, 7 b) are positioned close together in pairs to form asecond working containment space (S2) that is larger than the firstcontainment space (S1) defined by the first position.
 16. The machineaccording to claim 15, wherein, in the second operating position, onlyone group (7 b) of paddles (7) forms a respective space (S) forcontaining the product groups (4).
 17. The machine according to claim15, where the product groups (4) have a plurality of differentconfigurations according to a first dimension (LA) and included at leastbetween a first, single-layer configuration and a second, double-layerconfiguration of wrapped products (2); each first and secondconfiguration being subdivided into two or more sub-configurationsincluded between a first, minimum sub-configuration (LA1) in which eachproduct (2) has a first diameter (D1), and a second, maximumsub-configuration (LA2) in which each product (2) has a second diameter(D2) that is greater than the first diameter (D1), the machine beingwherein, at the first operating position, each paddle (7) of both groups(7 a, 7 b) forms a first working containment space (S1), defined as thedistance between two consecutive paddles (7), designed to permit thepassage and containment of the first configuration, including therespective sub-configurations between the first minimumsub-configuration (LA1) and the second, maximum sub-configuration (LA2).18. The machine according to claim 15, where the product groups (4) havea plurality of different configurations according to a first dimension(LA) and included at least between a first, single-layer configurationand a second, double-layer configuration of wrapped products (2); eachfirst and second configuration being subdivided into two or moresub-configurations included between a first, minimum sub-configuration(LA1) in which each product (2) has a first diameter (D1), and a second,maximum sub-configuration (LA2) in which each product (2) has a seconddiameter (D2) that is greater than the first diameter (D1), the machinebeing wherein, at the second operating position, each paddle (7) of onegroup (7 b) forms a second working containment space (S2), defined asthe distance between the working containment paddle (7) and the next orpreceding paddle (7) placed side by side with the next or precedingworking containment paddle (7), designed to permit the passage andcontainment of the second configuration, including the respectivesub-configurations between the first minimum sub-configuration (LA1) andthe second, maximum sub-configuration (LA2).
 19. The machine accordingto claim 15, wherein the first drive system (6 a) and the second drivesystem (6 b) each comprise at least: one pair (9 a, 9 b) of endlessdrive chains trained around a respective pair (10 a, 10 b) of toothedwheels kinematically connected to each other and to a single motor (11);the chains (9 a, 9 b) mounting the first group (7 a) and the secondgroup (7 b) of paddles (7), respectively; the adjustment means (8)acting between the pair of chains (9 a, 9 b) and the single motor (11).20. The machine according to claim 15, wherein the first drive system (6a) and the second drive system (6 b) each comprise: two pairs (9 a, 9 b)of endless drive chains trained around two respective pairs (10 a, 10 b)of toothed wheels kinematically connected to each other and to a singlemotor (11); the pairs (9 a, 9 b) of chains mounting the first group (7a) and the second group (7 b) of paddles (7), respectively; theadjustment means (8) acting between the two pairs of chains (9 a, 9 b)and the single motor (11).
 21. The machine according to claim 19,wherein the adjustment means (8) comprise a mechanical clutch (12)positioned and acting on the drive system (6 a) and designed to changebetween two separate states, in the first of which the clutch (12)simultaneously transmits drive to both the drive systems (6 a, 6 b),causing the groups (7 a, 7 b) of paddles (7) to move normally along theendless path (P6), and in the second of which the clutch (12) does nottransmit drive to the drive system (6 b), so as to keep the respectivegroup (7 b) of paddles (7) stationary while the group (7 a) of paddles(7) connected to the other drive system (6 a) moves in such a way as tovary its relative distance from the group (7 b) of paddles (7) betweenthe two relative operating positions.
 22. The machine according to claim21, wherein the mechanical clutch (12) can be operated manually.
 23. Themachine according to claim 21, wherein the mechanical clutch (12) can beoperated automatically from a panel (13) for controlling the machine(1).